Hello,
According to Section 44AD(1) an eligible person having turnover up to one crore from eligible business may adopt presumption income scheme by declaring his business income as 8 % of the turnover.
Further as per Section 44AD (5)
Notwithstanding anything contained in the foregoing provisions of this section, an eligible assessee who claims that his profits and gains from the eligible business are lower than the profits and gains specified in sub-section (1) and whose total income exceeds the maximum amount which is not chargeable to income-tax, shall be required to keep and maintain such books of account and other documents as required under sub-section (2) of section 44AA and get them audited and furnish a report of such audit as required under section 44AB.
So as per section 44AD(5) above, if eligible person having turnover less than 1 crore but profit claims to be less than 8% ,then Tax audit u/s 44AB is mandatory.